When copper is used as an internal conductor of a laminated coil component, it is necessary to co-fire a copper conductor and a ferrite material in a reducing atmosphere so that copper is not oxidized; however, there are problems such as that Fe in the ferrite material is reduced from trivalent to divalent and to decrease a resistivity of the laminated coil component when fired under such condition. Thus, in general, conductors composed mainly of silver have been used. However, it is preferable to use a conductor composed mainly of copper in light of its low resistance and good conductivity, as well as its inexpensiveness compared to silver.
WO 2011/108701 discloses a ceramic electronic component comprising a magnetic section formed from a ferrite material and a conductor section comprising copper as a main component, wherein the magnetic section contains a trivalent Fe and a divalent element(s) comprising at least divalent Ni, and wherein the magnetic section contains Mn in such an amount that a Fe content in terms of Fe2O3 is 20-48% as a molar ratio and that the ratio of Mn to the sum of Fe and Mn in terms of Mn2O3 and Fe2O3 is less than 50% (inclusive of 0%) as a molar ratio. According to WO 2011/108701, such composition can suppress a decrease in a resistivity of the ferrite material even when copper and the ferrite material are co-fired under a reducing atmosphere, and thus, inexpensive copper can be used as an internal conductor.